On 04/10/2015 15:11, Indy Jess John wrote:

If you have driven past a sign that shows 60, every working day for
years, would you really be confident of noticing one day that the 6 had
changed to a 5? I am a reasonably observant driver but I am not sure I
would, because my focus would be on the things that vary, the road and
the traffic, and not on something that had always been there.

You sure you'd not notice the difference between a 50 sign and the NSL
one? They're really quite different...